Woodworking machines utilize various means of positioning or securing a workpiece as it is cut, drilled or routed. As standard equipment a table saw normally has a rip fence for cuts parallel to the blade (ripping) and a miter gauge for cutting at an angle to the blade (crosscutting). The usual approach is to add a piece of plywood (or other wood board) to the table saw miter head, called an auxiliary fence, to provide a more stable surface to secure and control the workpiece. By cutting the excess material off the auxiliary fence, the workpiece is supported closely adjacent to the blade and there is less splintering and tear out at the edge of the cut when the blade breaks through the rear surface of the workpiece. An added benefit of this technique is that the operator knows that the end of the auxiliary fence adjacent to the blade is the cut line of the saw blade.
When cutting multiple pieces a small block of wood is often clamped to the auxiliary fence and is used to measure the distance between the distal end of the workpiece (where the cut is made) and the blade. Workpieces of identical lengths can then be cut. Some table saws are fitted with an aluminum extrusion which increases the surface area of the miter head and a metal flip stop is adjustably secured to the extrusion that flips out of the way when it is not in use. This is an improvement over the idea of clamping a piece of wood in place because the flip stop can be flipped out of the way when not in use and replaced instantly (by flipping it down to engage the workpiece) at exactly the same setting.
The radial arm saw utilizes a wood fence to position a workpiece in relationship to the blade. As with the table saw, a stop block is often clamped to the fence to measure the distance between the blade and the end of the board when cutting multiple pieces to exactly the same length. This technique eliminates the tedious task of lining up a mark on the workpiece with the saw blade. In addition, it is an advantage to have the fence be wood so that if the fence is repositioned relative to the blade, the blade can simply make a new cut through the fence, which decreases splintering and lets the operator know exactly where the cut line is. If the fence is moved away from the blade, a new longer fence can be provided and cut, since the wood material of the fence is inexpensive.
As standard equipment, miter saws usually have a small metal fence with holes so that a wood fence can easily be screwed to it to provide support similar to the wooden radial arm saw fence.
Drill press tables and router tables are usually quite small so that it is desirable and common to make a larger auxiliary table with scrap plywood being the material of choice because of its cost, dimensional stability and resistance to warp.
Shop made jigs and fixtures are made to hold and position a workpiece during cutting, drilling or routing operations. These jigs are usually made out of scrap wood with plywood being the material of choice.
Aftermarket woodworking accessories have also become very popular. These accessories are designed to replace the standard miter gauge on the table saw or the wood fence which is standard on the radial arm saw. Some of the accessories for portable miter saws are the same as those used on the radial arm saw. Another group of accessories is used on the router table and the drill press. However, there has been no jig, fixture or fence system that can be used on the table saw, band saw, radial arm saw, miter saw, router table, drill press and for shop made jigs and fixtures. Because none of the present systems are compatible with each other, the flip stop for a radial saw system will not fit the table saw, router table or drill press. This causes expensive duplication of equipment to equip all the various types of woodworking machinery with fixturing.
Replacement table saw miter gauges, radial arm saw and miter saw fences are known which are made with an aluminum extrusion to which the flip stop is attached. Problems arise because the metal of the fence or miter extension should not touch the saw blade. Therefore, the workpiece is not supported next to the saw blade with these known systems, creating tear out or splintering of the workpiece when the blade breaks through the rear surface. The operator is forced to align the mark on the workpiece with the blade rather than with the edge of the wood fence. When making mating angled cuts, the known aftermarket radial and miter saw fences must be reset so that the blade does not cut through the extrusion when the fence is moved from one side of the blade to the other.
High quality woodworking requires the ability to work in very close tolerances, preferably 0.004". Although some rip fences on table saws have adjusters for making fine adjustments, there is no system available with a microadjuster for moving a flip stop, miter gauge jig and/or fixture, or a fence on a router table or drill press. There are aftermarket fences available that move a fence in increments of 1/32 of an inch, which is too course for many high quality woodworking operations.
Flip stops that are currently available are not amenable to precise machine set ups. The stops are either stamped or cast and often deflect with pressure. None of the stops lock in place, so a sharp point, such as a 45 degree miter on the supported end of a workpiece, can slide behind the stop and move it forward, defeating its purpose. There is also no convenient means of quickly attaching an accessory which, for example, would extend the stop forwardly to abut an angled board which would otherwise slide past the front of the stop.
It is also sometimes desirable to provide a stop which is reversible, allowing it to be locked in place in the reversed position and thus be the platform for other accessories such as a fast action clamp which is often used for shop made jigs and fixtures. It is also useful to provide a double stop design which allows two closely spaced stop positions when crosscutting boards to length with the stop farthest from the blade functioning as the rough stop and the stop positioned nearest the blade acting as the finish stop.
Known jig and fixture systems for radial and miter saws have typically been different from systems for table saws, and from systems for drill presses and router tables so that the components of the systems could usually not easily be used interchangeably. In addition it was difficult to adapt them to be used with shop made jigs and fixtures.
A ruler is used on some of the aftermarket jig and fixture products to facilitate measuring when performing a cutting operation. There are self-adhesive rulers available but once these are stuck in place they are hard if not impossible to move. There is no mechanism for easily attaching a ruler to a shop made jig or fixture which allows a ruler to be moveable. It is desirable to provide a moveable ruler so that the jig can be "zeroed out" for different sized saw blades, router bits or drill bits.
Aftermarket table saw miter gauges are in general bigger and heavier versions of standard adjustable miter gauges, but in principle operate the same. Known miter gauges often have a guide bar which fits loosely in the table slot so that there is excessive play or "wiggle" of the bar in the slot. Some currently available guide bars are designed so that the bar is split with a slot and a screw expands the bar in the area of the slot. This design bulges the bar at one or two expansion points. The bar often wiggles in the slot when it is retracted for cutting a wide workpiece and the deformed bar makes it impossible to accurately square the miter head or jig and/or fixture against the bulged out side of the miter guide bar because that surface of the bar is not straight. There also is no lubrication provided in the currently available miter gauge bars or jig bars, requiring external lubrication.